New ortho-aniline-sulfonic acid



Patented July 11',

UNITED STATES PATENT l a I 1,917,441

ERIGI-I FISCHER, or BAD sonnn-on-rnn-rnunus, Ann ALBERT mssLrNG' AND" HERBERT KRACKER, F FRANKFORT-ON- THE-MAIN, GERMANY, .ASSIGNORS TO GEN-"1.,

ERAL ANILINE WORKS, INC., OF NEVJ YORK, N. Y., A CORPORATION DELAWARE V NEW ORTHO-ANILINE-SULFONIC ACID a No Drawing. Application filed ()ctober 14, 1930, Serial No. 488,698, and in Germany October 24;, 1929.

' wherein X stands for 7 may be applied in the present process. :It is J The present invention relates to new orthoanilinc-sulfonic acids.

We have found that new ortho-anilinesulfonic acids are obtainable by treating a primary aromatic amine of the following general formula I NHz X l alkyl, O-alkyl, O-aryl, O-aralkyl, CO-aryl, SO -ai'yl, N0 SO H, CQOH or halogen,with a molecular proportion of a halogen sulfonicjacid, advantageously in the presence of a diluent, moisture being: excluded. 7 i

The sulfonation occurs with very good yields. s

lVe prefer to use as diluents for instance aliphatic hydrocarbons of high boiling polnt, their lialogen substitution products, halogenated benzenes and toluenes, nitroben zene or the like. The examples show howthe diluent of essential importance for obtaining a good yield that any trace of moisture be excluded during'the sulfonation. p Q

'ibe new compounds obtainable by our;v process which v are valuable intermediate products for the synthesis of dye s tufi's of water.

various kinds correspond with the following general formula:

NHg.

ICOOH or halogen, and form crystal-line colorless powders which easily dissolve in The following examples serve to illustrate the invention, but they are not intended to limit it thereto, the parts being. by weight:

(1)176 parts of 4.6-dichloro-3-aniino-1- toluene are dissolvedlin about 700 parts of carbon tetrachloridef After addition of dehydrated copp'er'sulfate the solution is advantageously allowed to stand for about '12 hours so that even the smallest amount of water which might be present is removed. To the filtered solution there are added drop by drop within about half-an-hour 116.5 parts of chlorosulfonic acid while quickly stirring;' for this purpose an apparatus is.

used which is provided with 'a reflux condenser and'is protected as-much as possible against the entrance of moisture. Stirring is continued for some time and'the carbon tetrachloride is distilled oif while simultane- Thesulfonic can be isolated in one:

of the following manners: either the mixture is first filtered by suction, the residue is dissolved in water, the. solution is rendered feebly alkaline and :then distilled by means of steam, or. the wholemixture is distilled by means of steam after having been rendered alkaline. The diluentcan also be distilled in a vacuum and the sulfuric acid then transformed into the sodium'salt. From thefiltered solution of'the alkali salt the free 6- 'dichloro-3-amino-l-toluene z-sulfonic acid of the following probable formula NHz on n is is then separated bymeans of a. mineral acid. After it has been filtered by suction and dried it is a colorless powder, which scarcely dissolvesin water, easily dissolves in sodium carbonate, in the form of its sodium salt, and yields a diazo-compound scarcely soluble in water.

(2) 176 parts of 2.5-dichloro-4-amino-1- toluene are dissolved in about 2000 parts of ortho-dichlorobenzene. lVhile-yigorously stirring and well cooling 116.5 parts of chlorosulfonic acid are added drop by drop; stirring is continued for some time, and-the whole is then slowly heated to about 50 C., and subsequently the temperature is raised to 160 C.-170 C. Apparatus and conditions are the same as in Example 1.

The 2.5-dichloro-4-ainino l-tuluene-3 sultonic acid of the following probable formula 7 NH: i

HOaS o1" has properties similar to those-of the isomeric dichloro-toluidine-sulfonic acid described in Example 1.,

The 4,5-dichlOro-Q-ainino-l toluenes3-sulobtained in the same way from 4.5-dichloro- Q-ammo-l-tol'uene has similar propert es.

(3) By substituting for thew-(110111011) 3-amino1tolueno used in Example-'1, parts of pseudocuinidine there is obtained under the same conditions the 5111101110 acid,

ofthe following probable formula I V NHz which likewise is a colorless powder and SOaH the following OCH thus produced can'be recrystallized from water in the form of its sodium salt and is a colorless powder. -It yields a diazo-compound sparingly soluble in water.

T he two isomeric sulfonic acids of the following probable formulae have similar properties and are obtained in Y an analogous manner; l-amino-2-methoxyet-chloro-5-inethylbenzene required for thepreparation of" the former of these sulfonic acids.' may 'be'obtained by chlorination of 1- ace-tamino-Qunethoxy-fi-methylbenzene and tioned in the preceding examples 238.5 parts of 5-n1ethyl-l-chloro-Q-ainino-diphenyl ether (obtainable by condensation of 2.5-dichlorot-'nitro-'1-metliylbenzene with phenol and subsequent reduction of the intro-compound to'the amino-compound) there is obtained in cid of the fol:

like manner an ortho-sul'lonic a lowing probable formula yields a diaZo-compound. scarcely soluble in ,water.

( l) 171.5 parts of the product of the following formula i NH2 01 -(obtainable by chlorination of l-acetainino- In an analogous manner there are obtained subsequent elimination of the acetyl group;

(5) By si'ibstituting for the bases men-- other amino-di-phenyl-ether -sulfonie acids of the following probable formulae i I. V II. III.

ducing the nitro-group to the amino-group:v

-(6) By performing the operations de scribed in the-preceding examples upon 281.5 parts of a compound of the following formula (obtainable by condensation of'2l5-dichlor o- 4L -nitro-1-methylbenzene .with benzene sulfinic acid and subsequent reduction of the nitrogi"oup to the amino-compound), the, corresponding ortho-sulfonic acid of the following probable formula a V Hao l-chloro-5-nitro-1-methyl-2 methoxybenzenel responds with mula is obtained. I In the same way, for instance,-

the a minoarylsulfones of the following'for mulae undergo sulfonation at the place marked X i fol' - HaCO that is, it is immaterial whether ortho-, metaor para-amino-diarylsulfones are used.

The sulfones represented by theabove formulae may be obtained by condensation of benzene-sulfinic acid with 2-m-ethyl-5-chloro- 4c-nitro-l-methoxybenzene and 4.5-dichloro-' 2-methyl-1-nitrobenzene' respectively and subsequent reduction of the nitro-group to the amino-group.

(7) 167 parts of acompound of the following formula 0on3 (obtainable by causing 1 molecular proportion of 4.6 dichloro-Smitro-l-methylbenzene to react with 2 molecular proportions of so dium methylate, and subsequently reducing the nitro-compound to the amino-compound) are dissolved in about 1500 parts of orthodichloro-be'nzene and sulfonated as described in Example 2. The sulfonic acid, which corthe. following probable for- S0311 OGH3 V V I H30; V i V its can like-Wise here-crystallized from water in i ingly soluble diazo-compound.

1 (8) By performing the operations I dethe form ofits sodiumrsalt and yields a spar scribed in the precedingexamples upon 196,5 parts of 2.4.5-trichloro-aniline, thesulfonio acid I is obtained which is scarcelys'olublefin jwa ten but more readily. soluble ilr-theform of its-sodium salt; it yields a diam-compoundsparingly soluble in Water. V Y

(9) 266 parts of 2.5-dichloro-4 amino-benzophenone (obtainable by oxidizing 2:5-dichloro--nitro-1-methylbenzene to produce the corresponding l-carboxyl-ic acid, converting the latter into its acid chloride, condensing the 2.5-dichloro-4; nitro-1-benzoylchloride thus obtained with benzene in the presence of aluminium chloride and subsequently reducing the nitro-compound to the amino-compound) are transformed under the 95 conditions hereinbefore described'into the sulfonic acid of the following constitution In an analogous manner, for instance, the ammo-benzophenones of the following formulae, amongst others, undergo sulfonation at the places marked X moo that is to say, not only ortho-, but also mctaand para-amino-diarylketones are accessible to the said operation with good yield.

The amino-benzophenones represented by the above formulae I and II may be made as follows I. By" condensation of 4.6-dichloro-3-' nitro-1-benzoyl chloride with benzene by the Friedel-Crafts' reaction, -replacement of one halogen atom in the product by the methoxygroup, and reduction of the nitroggrou'p t the amino-group; I

y oxidation of 3.4edichloro-6-nitr'ol-methylbenzene to the; corresponding l-car- 'boxylic acid, conversion of the acid into its acid chloride, condensation of the 3.4-dichloro-6-nitro-1-benzoyl chloride thus obtained with benzene by the Friedel-Crafts reaction, and subsequent reduction of the initro-group to the amino-group.

(1O) 155.5 partsof a-compound of the following formula NH; I V

a c1 (obtainable by chlorination of acetyl-para- Xylidine and subsequent elimination of the acetyl grou'p) are dissolved in about 1500 partsiof nitrobenzene and thensulfonated under the conditions given in Example 1, whil'e the temperature advantageously is not allowed to rise above 160 C.-170 C. The

. reaction product corresponds with the following probableformula I SOaH I Cl v (1=1)-242 parts of 2.5-diehloraniline-4- sulfonic. acid (obtainable by baking 2.5-dichloraniline with sulfuric acid) are finely ground with 1000" parts oftetra-chloro-ethane to produce a suspension. This suspension ispoured into the 'sulfonati'on apparatus, 116.5 parts of chloro-sulfonic acid are added, and the whole is Worked up under the condit ions given in thepreceding examples. There is obtained the. disulfonic acid of the following probableformula: l

In this case the product. is preferably worked 01 are -NQ2 The sulfonic acid isapreferably isolated in the form of its sodium salt, which crystallizes from water.

(13) 206, parts of 2. 5-dichloro-4-amino-L benzoic acid are transformed under the conditions hereinbefore described into the sulfonic acid of the following constitution C1 SOaH l COOH The di-sodium salt is easily soluble in water; this sodium salt or the potassium salt may be crystallized from water.

Instead of the chloro-sulfonic acid used in the examples other halogen-sulfonic acids may be used; thus for instance, grams of fluoro-sulfonic acid may be substituted, with the same result, for the 116.5 grams of chloro-sulfonic acid.

lVe claim:

1. The compounds of the following general formula z I Y wherein X stands for methyl, methoXy, phenoxy, O-benzyl, benzoyl, SO pl1enyl or chlorine, Y for methyl, metho'xy, benzoyl, SO -phenyl, N0 SO H, COOH or chlorine, Z for methyl, benzoyl, or chlorine, being crystalline colorless powders dissolving in water.

2. The compound of the following probable formula 01 SOBOH I CH3 Cl being a colorless crystalline powder, dissolv- 1ng 1n water and 1n sodium carbonate.

3. The compound of the following probable formula ,7

NHg 01 l scion being a colorless crystalline powder, dissolving in water and in sodium carbonate. 7 4. The compound of the following prob-i able formula V NHz or d so ou being a colorlesscrystalline powder, dissolving in water andin sodium carbonate.

5. The compounds of the following -gen-' eral formula:

NHa

X soion wherein 'X stands for chlorine, methyl, me-

thoxy or phenoX-y, Y represents chlorine, methyl or methoXy, and Z means chlorine or methyl, said products being colorless powders soluble in water.

6. The compounds of the following general formula X soion 

